import java.util.*;
class Example2_5 {
	public static void main(String args[]) {
	  int start = 0,end,middle;
	  int a[] = {12,45,67,89,123,-45,67,5233};
	  int N = a.length;
	  for(int i=0; i < N; i++) {
	  for(int j =i+1 ;j < N; j++) {
	       if(a[j] < a[i]){
	          int t = a[j];
	          a[j] = a[i];
	          a[i] = t;
	       }
	    }
	  }
    Scanner scanner = new Scanner(System.in);
    System.out.println("输入整数，程序判断该整数是否在数组中:");
    int number = scanner.nextInt();
    int count = 0;
    end = N;
    middle=(start+end)/2;
    while(number!=a[middle]){
        if(number>a[middle])
          start=middle;
        else if(number<a[middle])
          end=middle;
        middle = (start+end)/2;
        count++;
        if(count>N/2)
          break;
    }
    if(count>N/2)
      System.out.printf("%d不在数组中.\n",number);
    else
      System.out.printf("%d在数组中.\n",number);
	}
}